The paper is devoted to theoretical and experimental investigations of Lamb wave excitation and propagation in multilayered carbon fiber-reinforced plastic plates with obstacles. The theoretical modeling is performed in the context of general linear elasticity for three-dimensional laminate anisotropic media. It is based on the integral and asymptotic representations in terms of Green’s matrix ...

The results of Lamb wave identification for the aerospace structures could be easily affected by the nonlinear-dispersion characteristics. In this paper, dispersion compensation of Lamb waves is of particular concern. Compared with the similar research works on the traditional signal domain transform methods, this study is based on signal construction from the viewpoint of nonlinear wavenumber ...

Piezoelectric wafer active sensors (PWAS) used in structural health monitoring (SHM) applications are able to detect structural damage using Lamb waves. PWAS are small, lightweight, unobtrusive and inexpensive. PWAS achieve direct transduction between electric and elastic wave energies. PWAS are essential elements in the Lamb-wave SHM with pitch-catch, pulse-echo, phased array system and electr...

We demonstrate both theoretically and experimentally the physical mechanism that underlies extraordinary acoustic transmission and collimation of sound through a one-dimensional decorated plate. A microscopic theory considers the total field as the sum of the scattered waves by every periodically aligned groove on the plate, which divides the total field into far-field radiative cylindrical wav...

The Tonga volcano erupted on 15 January 2022, at 04:15:45 UTC, which significantly influenced the atmosphere and space environment, same time, an unprecedented opportunity to monitor ionospheric anomalies is provided by its powerful eruption. In current studies of traveling disturbance (TID) triggered 2022 volcanic eruption, particular phenomenon disturbances in various parts world has not been...

The objectives of the thesis work were to study the interaction between embedded piezoceramic transducers and composite structures as well as determine techniques to simplify the Lamb waves analysis. Firstly, this study considered the design of the embedded piezoceramic transducers. Secondly, the effect of the embedded transducer on the composite strength as well as the influence of the mechani...

Lamb waves have been reported to be an efficient tool for non-destructive evaluations (NDE) for various application scenarios. However, accurate and reliable damage quantification using the Lamb wave method is still a practical challenge, due to the complex underlying mechanism of Lamb wave propagation and damage detection. This paper presents a Lamb wave damage quantification method using a le...

This paper proposes a novel Lamb wave line sensing technique for crack detection in a welded stiffener. The proposed technique overcomes one of the biggest technical challenges of Lamb wave crack detection for real structure applications: crack-induced Lamb waves are often mixed with multiple reflections from complex waveguides. In particular, crack detection in a welded joint, one of the struc...

2014 An overview is given describing the physical basis of ultrasonic reflectivity as it relates to solid material characterization. The examples given illustrate critical angle reflection, Rayleigh and Lamb waves, and crystal orientation via reflection measurements. Revue Phys. Appl. 20 (1985) 377-381 JUIN 1985, PAGE Classification Physics Abstracts 43.20

The objective is to develop a hybrid one-dimensional finite element (FE)/analytical method to analyze the Lamb Wave propagation characteristics in a composite panel for the purpose of detecting the specific structural defects in the composite panel. Here, it is proposed to use a composite panel using a finite element approximation in the thickness direction while wave solutions are assumed in t...